Valor pronóstico de la ecocardiografía en pico de ejercicio en cinta rodante en pacientes con ergometría convencional negativa y en otros subgrupos clínicamente relevantes

[Resumen] Antecedentes y objetivos: El valor pronóstico de la ecocardiografía de ejercicio en pacientes con ergometría convencional normal no ha sido evaluado. Nuestro objetivo fue estudiar el valor de la ecocardiografía de ejercicio para predecir mortalidad y eventos cardiacos graves en pacientes con enfermedad coronaria conocida o sospechada y ergometría convencional negativa. Métodos: Estudiamos a 4004 pacientes consecutivos (2358 hombres, edad media 59,6±12,5 años) con electrocardiograma basal interpretable que fueron sometidos a ecocardiografía de ejercicio en cinta rodante y no desarrollaron dolor torácico o cambios ECG isquémicos durante los tests. Se calculó un índice de motilidad segmentaria (IMS) en reposo y en ejercicio así como la diferencia entre ambos valores (?IMS). La isquemia se definió como el desarrollo de nuevas alteraciones de la contractilidad segmentaria o empeoramiento de las previamente presentes. Los endpoints fueron mortalidad total y eventos cardiacos graves (muerte cardiaca o infarto no fatal). Resultados: En total, 669 pacientes (16,7%) desarrollaron isquemia con el ejercicio. Durante un seguimiento de 4,5±3,4 años, 313 pacientes fallecieron, y 183 pacientes presentaron un evento cardiaco grave antes de cualquier procedimiento de revascularización coronaria. La tasa de mortalidad y de eventos cardiacos graves a 5 años fue del 6,4% y 4,2% en pacientes sin isquemia frente al 12,1% y 10,1% en aquellos con isquemia, respectivamente (p <0,001). En el análisis multivariado, el ?IMS resultó predictor independiente de mortalidad (hazard ratio [HR] 2,73, intervalo de confianza [IC] del 95% 1,40-5,32, p = 0,003) y de eventos cardiacos graves (HR 3,59, IC 95% 1,42-9,07, p = 0,007) e incrementó el ?2 global de los modelos para la predicción de mortalidad (p = 0,005) y de eventos cardiacos graves (p = 0,009). Conclusiones: La ecocardiografía de ejercicio proporciona información pronóstica significativa para la predicción de mortalidad y eventos cardiacos graves en pacientes con electrocardiograma interpretable y ergometría convencional normal.[Resumo] Antecedentes e obxectivos: O valor pronóstico da ecocardiografía de exercicio en pacientes cunha ergometría convencional normal non foi avaliado. O noso obxectivo foi estuda-lo valor da ecocardiografía de exercicio para predicir mortalidade e eventos cardíacos graves en pacientes con enfermidade coronaria coñecida ou sospeitada e cunha ergometría convencional negativa. Métodos: Estudamos a 4004 pacientes consecutivos (2358 homes, idade media 59,6±12,5 anos) cun electrocardiograma basal interpretable que foron sometidos a ecocardiografía de exercicio en cinta rodante e non desenrolaron dor torácica ou cambios electrocardiográficos isquémicos durante os tests. Calculouse un índice de motilidade segmentaria (IMS) en repouso e en exercicio así como a diferenza entre ambos valores (?IMS). A isquemia definiuse coma a aparición de novas alteracións da contractilidade segmentaria ou o empeoramento das previamente presentes. Os endpoints foron a mortalidade total e os eventos cardíacos graves (morte cardíaca ou infarto non fatal). Resultados: En total, 669 pacientes (16,7%) desenrolaron isquemia co exercicio. Durante un seguimento de 4,5±3,4 años, 313 pacientes faleceron, e 183 pacientes presentaron un evento cardíaco grave antes de calquera procedemento de revascularización coronaria. A tasa de mortalidade e de eventos cardíacos graves a 5 anos foi do 6,4% e 4,2% en pacientes sen isquemia fronte ó 12,1% e 10,1% en aqueles con isquemia, respectivamente (p <0,001). No análise multivariado, o ?IMS resultou predictor independente de mortalidade (hazard ratio [HR] 2,73, intervalo de confianza [IC] do 95% 1,40-5,32, p = 0,003) e de eventos cardíacos graves (HR 3,59, IC 95% 1,42-9,07, p = 0,007) e incrementou o valor do ?2 global dos modelos para a predición de mortalidade (p = 0,005) e de eventos cardíacos graves (p = 0,009). Conclusións: A ecocardiografía de exercicio proporciona información pronóstica significativa para a predición de mortalidade e de eventos cardíacos graves en pacientes con electrocardiograma interpretable e ergometría convencional normal.[Abstract] Background and objectives: The prognostic value of exercise echocardiography in patients with normal exercise electrocardiographic testing has not been characterized. Our aim was to assess the value of exercise echocardiography for predicting outcome in patients with known or suspected coronary artery disease and normal exercise electrocardiogram. Methods: We studied 4004 consecutive patients (2358 men, mean age [± SD] 59.6±12.5 years) with interpretable electrocardiograms who underwent treadmill exercise echocardiography and did not develop chest pain or ischemic electrocardiographic abnormalities during the tests. Wall motion score index (WMSI) was evaluated at rest and with exercise, and the difference (?WMSI) was calculated. Ischemia was defined as the development of new or worsening wall motion abnormalities with exercise. End points were all-cause mortality and major cardiac events. Results: Overall, 669 patients (16.7%) developed ischemia with exercise. During a mean follow-up of 4.5±3.4 years, 313 patients died, and 183 patients had a major cardiac event before any revascularization procedure. The 5-year mortality and major cardiac event rates were 6.4% and 4.2% in patients without ischemia vs. 12.1% and 10.1% in those with ischemia, respectively (p<0.001). In the multivariate analysis, ?WMSI remained an independent predictor of mortality (hazard ratio [HR] 2.73, 95% confidence interval [CI] 1.40-5.32, p=0.003) and major cardiac events (HR 3.59, 95% CI 1.42-9.07, p=0.007). The addition of the exercise echocardiography results to the clinical, resting echocardiographic and exercise hemodynamic data significantly increased the global ?2 of the models for the prediction of mortality (p=0.005) and major cardiac events (p=0.009). Conclusions: Exercise echocardiography provides significant prognostic information for predicting mortality and major cardiac events in patients with interpretable electrocardiogram and normal exercise electrocardiographic testing

Prognostic Value of Treadmill Exercise Echocardiography

[Abstract] Introduction and objectives. Exercise echocardiography (EE) is useful for diagnosing coronary disease, but little is known about its value for risk stratification. We aimed to determine: a) whether data from EE supplemented clinical data and data from exercise testing and resting echocardiography in predicting cardiac events; and b) whether the number and location of abnormal regions and their responses to exercise influenced risk stratification. Patients and method. The 2,436 patients referred for EE were followed up for 2.1 ±1.5 years. Some 120 serious cardiovascular events (i.e., non-fatal myocardial infarction or cardiovascular death) occurred before revascularization. Results. In 1203 patients (49%), EE gave abnormal results. There were 89 events in patients with an abnormal result (7.3%) and 31 in those with a normal result (2.5%; P <.0001). Multivariate analysis of clinical data, and data from exercise testing, resting echocardiography, and EE showed that male sex (RR=1.7; 95% CI, 1.1–2.8; P = .02), metabolic equivalents or METs (RR=0.9; 95% CI, 0.86–0.98; P=.01), peak heart rate × blood pressure (RR= 0.9; 95% CI, 0.9; P=.002), resting wall motion score index (RR=2.5; 95% CI, 1.5–4.1; P <.0001), and number of abnormal regions at peak exercise (RR=1.4; 95% CI, 1.2–1.7; P<.0001) were independently associated with the risk of a serious event (final model χ2, 170; incremental P <.0001). The same variables, excluding sex, were independently associated with cardiovascular death (final model χ2, 169; incremental P = .01). Conclusions. Exercise echocardiography supplements clinical data and data from exercise testing and resting echocardiography in patients with known or suspected coronary artery disease.[Resumen] Introducción y objetivos. Aunque la ecocardiografía de ejercicio es útil para el diagnóstico de la enfermedad coronaria, hay menos datos referentes a su valor pronós-tico. El objetivo de este estudio fue esclarecer: a) si hay un valor incremental de la ecocardiografía en el pico del ejercicio respecto a las variables clínicas, la prueba de esfuerzo y la ecocardiografía en reposo, y b) si el número y la localización de los territorios afectados, así como el tipo de respuesta al ejercicio, influyen en la estratificación. Pacientes y método. En 2.436 pacientes referidos para ecocardiografía de ejercicio se realizó un seguimien-to de 2,1 ± 1,5 años. Hubo 120 eventos (infarto no fatal o muerte cardiovascular) antes de la revascularización. Resultados. La ecocardiografía fue anormal en 1.203 pacientes (49%). Hubo 89 eventos en pacientes con resul-tado anormal (7,3%) frente a 31 con resultado normal (2,5%; p < 0,001). Mediante un análisis multivariable de variables clínicas, de la prueba de esfuerzo y de la ecocardiografía en reposo y ejercicio encontramos que las variables asociadas de manera independiente con el riesgo de eventos eran: ser varón (riesgo relativo [RR] = 1,7; interva-lo de confianza [IC] del 95%, 1,1–2,8; p = 0,02), los equiva-lentes metabólicos o MET (RR = 0,9; IC del 95%, 0,9–1,0; p = 0,01), el producto frecuencia cardíaca × presión arterial (RR = 0,9; IC del 95%, 0,9–1,0; p = 0,02), el índice de moti-lidad segmentaria basal (RR = 2,5; IC del 95%, 1,5–4,1; p < 0,0001) y el número de territorios afectados (RR = 1,4; IC del 95%, 1,2-1,7; p < 0,0001) (χ2 final = 170, valor incremental de la ecocardiografía en el máximo esfuerzo; p < 0,0001). Las mismas variables, excepto el sexo, estaban asociadas con la muerte (χ2 final = 169, valor incremental de la ecocardiografía de ejercicio; p = 0,01). Conclusiones. La ecocardiografía en el máximo ejercicio incrementa el valor pronóstico de las variables clínicas, la prueba de esfuerzo y la ecocardiografía de reposo

Fate of endocrine disruptor compounds in an anaerobic membrane bioreactor (AnMBR) coupled to an activated sludge reactor

[EN] The occurrence and fate of three groups of micropollutants - alkylphenols, pentachlorophenol and hormones - were studied in a pilot plant consisting of an anaerobic membrane bioreactor (AnMBR) coupled to an activated sludge reactor (University of Cape Town configuration - UCT). Under anaerobic conditions, the octylphenol and technical-nonylphenol soluble concentrations increased producing negative degradation ratios (i.e., -175 and -118%, respectively). However, high 4-n-nonylphenol and bisphenol-A degradation ratios (92 and 59% for 4-n-nonylphenol and bisphenol-A, respectively) as well as complete pentachlorophenol, estrone, 17 beta-estradiol and 17 alpha-ethinylestradiol removal were observed. Under aerobic conditions (UCT), octylphenol, technical-nonylphenol, 4-n-nonylphenol and bisphenol-A degradation ratios were higher than 84%. The AnMBR thus removes a high proportion of 4-n-nonylphenol, pentachlorophenol, estrone, 17 beta-estradiol and 17 alpha-ethinylestradiol, but requires a later post-treatment process (such as UCT) to improve bisphenol-A, octylphenol and technical-nonylphenol degradation ratios. The overall AnMBR-UCT degradation ratios were 48% and 70% for octylphenol and technical-nonylphenol, respectively, and higher than 97% for 4-n-nonylphenol and bisphenol-A. The AnMBR produced a higher micropollutant accumulation in the sludge than the UCT: removal by adsorption in the AnMBR process was between 0.5 and 10%, and less than 0.5% in the UCT process. The combination of AnMBR and UCT technologies produces an effluent stream with low concentrations of micropollutants.This work was supported by the Spanish Ministry of Economy and Competitiveness (MINECO, CTM2011-28595-C02-01 and CTM2011-28595-C02-02) and the European Regional Development Fund (ERDF).Abargues Llamas, MR.; Ferrer, J.; Bouzas Blanco, A.; Seco Torrecillas, A. (2018). Fate of endocrine disruptor compounds in an anaerobic membrane bioreactor (AnMBR) coupled to an activated sludge reactor. Environmental Science: Water Research & Technology (Online). 4(2):226-233. https://doi.org/10.1039/c7ew00382jS2262334

P-recovery in a pilot-scale struvite crystallisation reactor for source separated urine systems using seawater and magnesium chloride as magnesium sources

[EN] Practical recovery of a non-renewable nutrient, such as phosphorus (P), is essential to support modern agriculture in the near future. The high P content of urine, makes it an attractive source for practicing the recovery of this crucial nutrient. This paper presents the experimental results at pilot-plant scale of struvite crystallisation from a source-separated urine stream using two different magnesium sources, namely magnesium chloride and seawater. The latter was chosen as sustainable option to perform P-recovery in coastal areas. Real seawater was used to assess in a more realistic way its efficiency to precipitate P as struvite, since its composition (with noticeable concentration of ions such as Ca2+, SO42¿, Na+, ¿) could lead to the formation of impurities and other precipitates. 0.99¿g of struvite was obtained per litre of urine irrespective of the operational conditions tested. In all tested conditions, precipitation efficiencies exceeded 90% and recovery efficiencies were higher than 87%, with an average struvite crystal size higher than 110¿¿m (and up to 320¿¿m, depending on the experimental conditions) in the harvested struvite samples. Almost pure struvite was obtained when MgCl2 was used as precipitant, while amorphous calcium phosphate and other impurities appeared in the precipitates using seawater as magnesium source. However, the lower settling velocity of the amorphous precipitates in comparison with the struvite precipitates suggests that their separation at industrial scale could be relatively straightforward.This research work was possible thanks to FCC Aqualia participation in INNPRONTA 2011 IISIS IPT-20111023 project (partially funded by The Centre for Industrial Technological Development (CDTI) and supported by the Spanish Ministry of Economy and Competitiveness).Aguado García, D.; Barat, R.; Bouzas Blanco, A.; Seco Torrecillas, A.; Ferrer, J. (2019). P-recovery in a pilot-scale struvite crystallisation reactor for source separated urine systems using seawater and magnesium chloride as magnesium sources. The Science of The Total Environment. 672:88-96. https://doi.org/10.1016/j.scitotenv.2019.03.485S889667

Micropollutants removal in an anaerobic membrane bioreactor and in an aerobic conventional treatment plant

The paper expresses an attempt to tackle the problem due to the presence of micropollutants in wastewater which may be able to disrupt the endocrine system of some organisms. These kinds of compounds are ubiquitously present in municipal wastewater treatment plant (WWTP) effluents. The aim of this paper is to compare the fate of the alkylphenols-APs (4-(tert-octyl)) phenol, t-nonylphenol and 4-p-nonylphenol and the hormones (estrone, 17ß-estradiol and 17¿-ethinylestradiol) in a submerged anaerobic membrane bioreactor (SAMBR) pilot plant and in a conventional activated sludge wastewater treatment plant (CTP). The obtained results are also compared with the results obtained in a previous study carried out in an aerobic MBR pilot plant. The results showed that the APs soluble concentrations in the SAMBR effluent were always significantly higher than the CTP ones. Moreover, the analyses of the suspended fraction revealed that the AP concentrations in the SAMBR reactor were usually higher than in the CTP reactor, indicating that under anaerobic conditions the APs were accumulated in the digested sludge. The aerobic conditions maintained both in the CTP system and in the aerobic MBR favoured the APs and hormones degradation, and gave rise to lower concentrations in the effluent and in the reactor of these systems. Furthermore, the results also indicated that the degradation of APs under aerobic conditions was enhanced working at high solid retention time (SRT) and hydraulic retention time (HRT) values. © IWA Publishing 2012.This research was financially supported by the Government of the Region of Valencia (Generalitat Valenciana), within the research project 'Application of Water Framework Directive 2000/60/EC on endocrine disruptors and priority substances in coastal areas in the Comunidad Valenciana' and by the Spanish Research Foundation (MICINN, project CTM2008-060809-C02-01/TECNO), within the research project 'Feasibility of the SAMBR technology to treat urban wastewater, and the technical and economic feasibility to industrial implementation'.Agargues Llamas, MR.; Robles Martínez, Á.; Bouzas Blanco, A.; Seco Torrecillas, A. (2012). Micropollutants removal in an anaerobic membrane bioreactor and in an aerobic conventional treatment plant. Water Science and Technology. 65(12):2242-2250. doi:10.2166/wst.2012.145S22422250651

Use of rumen microorganisms to boost the anaerobic biodegradability of microalgae

[EN] A laboratory bioreactor using rumen microorganisms to treat Scenedesmus spp. biomass was operated for 190 days. At first the bioreactor operated as a Rumen-like Fermenter (RF) with a Sludge Retention Time (SRT) of 7 days. The RF was subsequently transformed into an anaerobic digestion system including two configurations: continuously-stirred tank reactor and anaerobic membrane bioreactor in which different SRT values of up to 100 days were assessed. Methane production peaked at 214 mL CH4 g&#8722;1 CODIn with a SRT of 100 days. COD removal and BDP peaked at above 70% and 60%, respectively, at the highest SRT, with no pre-treatment prior to microalgae digestion. The waste sludge production dropped to 0.133 mg VSS mg&#8722;1 CODIn after a SRT of 100 days.This work was funded by the Spanish Ministry of Economy and Competitiveness with the support from the European Commission through the European Regional Development Funds (MINECO, CTM2011-28595-C02-01 and CTM2011-28595-C02-02), which are gratefully acknowledged. The authors would also express their gratitude to the Education, Invetigation, Culture and Sports Council from the Valencian Generality for the Post-Doctoral fellowship awarded to Juan Bautista Gimenez Garcia (APOSTD/2016/104). The authors are thankful to Ion Perez Baena (Universitat Politecnica de Valencia, Institut de Ciencia i Tecnologia Animal) for kindly providing the ruminal fluid used in this study.Gimenez, JB.; Aguado García, D.; Bouzas, A.; Ferrer, J.; Seco Torrecillas, A. (2017). Use of rumen microorganisms to boost the anaerobic biodegradability of microalgae. Algal Research. 24:309-316. https://doi.org/10.1016/j.algal.2017.04.0033093162

Sludge management modeling to enhance P-recovery as struvite in wastewater treatment plants

[EN] Interest in phosphorus (P) recovery and reuse has increased in recent years as supplies of P are declining. After use, most of the P remains in wastewater, making Wastewater Treatment Plants (WWTPs) a vital part of P recycling. In this work, a new sludge management operation was studied by modeling in order to recover Pin the form of struvite and minimize operating problems due to uncontrolled P precipitation in WWTPs. During the study, intensive analytical campaigns were carried out on the water and sludge lines. The results identified the anaerobic digester as a "hot spot" of uncontrolled P precipitation (9.5 gP/kg sludge) and highlighted possible operating problems due to the accumulation of precipitates. A new sludge line management strategy was simulated therefore using DESASS (c) software, consisting of the elutriation of the mixed sludge in the mixing chamber, to reduce uncontrolled P precipitation and to obtain a P-rich stream (primary thickener supernatant) to be used in a crystallization process. The key operating parameters were found to be: the elutriation flow from the mixing chamber to the primary thickener, the digestion flow and the sludge blanket height of the primary thickener, with optimized values between 70 and 80 m(3)/d, 90-100 m(3)/d and 1.4-1.5 m, respectively. Under these operating conditions, the preliminary results showed that P concentration in the primary thickener overflow significantly increased (from 38 to 100 mg PO4-P/L), which shows that this stream is suitable for use in a subsequent crystallization reactor to recover P in the form of struvite. (C) 2017 Elsevier Ltd. All rights reserved.This work was co-financed by the European Financial Instrument for the Environment (LIFE +) as part of the PHORWater Project (LIFE12 ENV/ES/000441).Martí Ortega, N.; Barat, R.; Seco Torrecillas, A.; Pastor Alcañiz, L.; Bouzas Blanco, A. (2017). Sludge management modeling to enhance P-recovery as struvite in wastewater treatment plants. Journal of Environmental Management. 196:340-346. https://doi.org/10.1016/j.jenvman.2016.12.074S34034619

Momento Económico (21)

En este número Temas de hoy, 2/ Los recursos financieros del gobierno mexicano en 1986, Marcela Astudillo, 3/ La deuda pública en el presupuesto para 1986, Constantino Pérez Morales, 6/ El caos petrolero en los años ochenta: ¿hacia un nuevo contexto de lucha?, Sergio Suárez Guevara, 10/ Costureras e industria de la confección, Lucia Alvarez Mosso, 14/ El sismo fracturó también las instituciones normativas de la sociedad mexicana. José Alfonso Bouzas, 1

Implementation of a global P-recovery system in urban wastewater treatment plants

[EN] Current wastewater treatment plants (WWTPs) paradigm is moving towards the so-called water resource recovery facilities in which sewage is considered a source of valuable resources. In particular, urban WWTPs are crucial systems to enhance phosphorus (P) recycling. This paper evaluates the implementation of a P-recovery system in Calahorra WWTP combining the operation of a new sludge line configuration coupled to a struvite crystallisation reactor at demonstration-scale. This new configuration consisted in the elutriation in the gravity thickener of the mixed sludge contained in the mixing chamber in order to reduce the phosphate load to the anaerobic digestion. The results indicated that the P available in the primary sludge overflow was nearly five times more than the obtained for the conventional configuration (1.88 vs. 0.39 gP/kg sludge treated), and the uncontrolled P precipitation inside the anaerobic digester was reduced by 43%. Regarding the total P entering the WWTP, 19% of the total P could be recovered with the new configuration proposed in comparison with 9% in the previous conventional configuration. The average recovery efficiency in the crystallisation plant was 86.9 0.4%, yielding a struvite recovery of 8.0 +/- 0.6 kg/d (0.67 +/- 0.04 kg/m(3) fed to the crystalliser). The potential struvite production with the new configuration would be around 41 kg/d (15 t/y) crystallising the thickener supernatant which could be increased up to around 103 kg/d (38 t/y) treating all the P enriched streams (thickener supernatant and centrate streams). The paper demonstrates that WWTPs can contribute to reduce P scarcity, resulting in environmental and economic benefits. (C) 2019 Elsevier Ltd. All rights reserved.This work was co-financed by the European Financial Instrument for the Environment (LIFE +) as part of the PHORWater Project (LIFE12 ENV/ES/000441). The authors also like to acknowledge the support received from Consorcio de Aguas y Residuos de La Rioja and from EDAR del Cidacos (Calahorra).Bouzas Blanco, A.; Martí Ortega, N.; Grau, S.; Barat, R.; Mangin, D.; Pastor Alcañiz, L. (2019). Implementation of a global P-recovery system in urban wastewater treatment plants. Journal of Cleaner Production. 227:130-140. https://doi.org/10.1016/j.jclepro.2019.04.126S13014022